I am installing a xb14 trane condenser and I recently learned that the joints should be silver soldered with nitrogen flowing. I work on cars and have experience with HVAC but not residential. Can I use my argon gas that I use to mig weld with to purge the lines? Also, how is the gas introduced to the lines and where does it come out when I am soldering the last joint?
Can I use an infrared temperature gun to measure the temperature of the lines to calculate sub cooling. This is all new to me because with auto AC you just add the recommended amount of freon on the label under the hood.
You don't need nitrogen with silver solder. (ex: Harris Stay Silv). It also produces a stronger joint then brazing. However it's best suiting for brand new joints, requires flux and is rather unforgiving to bad technique/joint prep.
If you choose to braze (ex: sil phos) then you need nitrogen due to the higher heat involved. I think most guys pull the schraders out of the service valves for the flow to exit. I don't see why argon wouldn't work. You just need an inert gas to displace oxygen which would otherwise contaminate the system.
There's a great you tube video that shows what happens when you braze without Nitrogen.